The authenticity of host '10.0.0.228 (10.0.0.228)' can't be established.
ECDSA key fingerprint is SHA256:a6aknOruK4Or1IjIZbgYgp+IswyON5L7gjQtGpG0SVw.
ECDSA key fingerprint is MD5:1f:b0:09:b7:eb:3b:54:ff:3f:e2:9d:b3:46:20:08:e7.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '10.0.0.228' (ECDSA) to the list of known hosts.

[centos@centos-7 ~]$

# just logined

[4]

If you'd like to stop an instance, it's also possible to control with openstack command like follows.